Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physics of the Solid State

Investigation of the regimes of mixing of superconducting tunneling structures

K. V. Kalashnikov, Anton A. Artanov, Lyudmila V. Filippenko, V. P. Koshelets

Published Nov 1, 2016• 2 citations
Publisher

Abstract

The regimes of operation of a superconductor–insulator–superconductor tunnel junction based on three-layer structures Nb/AlOx/Nb and Nb/AlN/NbN as a harmonic mixer (for frequencies of the order of 600 and 20 GHz, respectively) and a frequency up-converter (in the frequency range from 0.1 to 5.0 GHz) have been investigated experimentally. The quasiparticle and Josephson mixing regimes have been compared. It has been shown that, in some practical applications, such as the use of the superconductor–insulator–superconductor junction as a cryogenic harmonic phase detector, the Josephson mixing regime is more preferable, because it can provide a higher signal and a greater signal-to-noise ratio as compared to the quasiparticle mixing regime. It has also been demonstrated that the Josephson mixing regime is promising for the use in signal multiplexing systems for superconducting detectors.

DOI
10.1134/s1063783416110135

Related papers

Investigation of the Harmonic Mixer and Low-Frequency Converter Regimes in a Superconducting Tunnel Junction

K. V. Kalashnikov, Anton A. Artanov, Gert J. de Lange +1 more

We experimentally investigate different mixing regi-mes in Nb/AlOx/Nb and Nb/AlN/NbN tunnel superconductor-insulator-superconductor (SIS) junctions. The SIS mixers were studied with regard to the following modes of operation: in an extremely low-frequency range (0.1-20 GHz) and as high harmonic mixers; n ≈ 20-30 at signal frequencies of about 500 GHz that requires high power of a local oscillator. The quasiparticle and Josephson mixing regimes have been compared. We demonstrate that, in some applications requiring high conversion efficiency, the Josephson regime can be more preferable than the quasiparticle regime due to a larger output signal and better signal-to-noise ratio. As an example of such an application, we consider the phase locking of a THz oscillator using a cryogenic harmonic phase detector, which only ought to realize all of its benefits under the Josephson mixing regime. In addition, we demonstrate that the presence of the Josephson effect results in considerable increase in conversion efficiency at the expense of the dynamic range decrease; it was measured for low-frequency up- and down-convertors, which are promising for cryogenic multiplexing systems.

IEEE Transactions on Applied Superconductivity•Feb 6, 2018•6 citations

Tunnel superconducting junctions for a cryogenic multiplexing system

Anton A. Artanov, K. V. Kalashnikov, V. P. Koshelets +1 more

the possibility of using superconductor–insulator–superconductor (SIS) tunnel junctions in a cryogenic multiplexing system for setting an ac current through arrays of transition edge sensors and reading out the received signal, as well as for setting a dc current through arrays of superconducting quantum interferometers is studied. Operation of the SIS frequency converter at relatively low (below 10 GHz) working frequencies is experimentally investigated. Different operation regimes are implemented; the conversion loss in the quasiparticle mode is found to be 8 dB and the output saturation power is–58 dBm. The possibility of up-conversion of several input signal frequencies simultaneously is demonstrated. It is shown that the SIS junction can be used as a current source controlled by an external RF signal.

Journal of Communications Technology and Electronics•Sep 1, 2016•1 citation

0.5-THz waveguide SIS mixers with NbN/AlN/NbN technology

Jing Li, Masanori Takeda, Zhen Wang +1 more

Heterodyne mixers based on superconducting SIS (superconductor-insulator-superconductor) tunnel junctions have been demonstrated to be the most sensitive coherent detectors at millimeter and submillimeter wavelengths. In fact, conventional superconducting SIS mixers with Nb/AlOx/Nb junction and Nb/SiO2/Nb tuning circuit have shown good performances with the noise temperature reaching as low as three times the quantum limit below 0.7THz, which is the gap frequency of Nb-based SIS junctions. However, due to the large loss in Nb thin-film superconducting microstrip lines, the noise performance of Nb SIS mixers deteriorates significantly above 0.7THz. With a gap frequency double that of Nb-based SIS junctions, NbN-based SIS junctions are of particular interest for the development of heterodyne mixers in the terahertz region. Considering the bandwidth and output power of local-oscillator (LO) signal sources are quite limited around 1THz, we firstly develop a waveguide NbN-based SIS mixer at 0.5THz. Three types of SIS junctions, i.e., long junction, parallel-connected tunnel junction (PCTJ) and distributed junction array (DJ) are investigated. They are all comprised of NbN-AlN-NbN tri-layer fabricated on an MgO substrate and have the same current density (Jc) of 10kA/cm2. In this paper, we describe their design, fabrication and preliminary experimental results.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 29, 2007•3 citations

Superconductor–insulator–superconductor tunnel strip line: Features and applications

Victor Y. Belitsky, E. Kollberg

The superconductor–insulator–superconductor (SIS) tunnel junction based on Nb material has been investigated theoretically at frequencies of 200–1400 GHz by modeling it as a segment of a superconducting microstrip transmission line and using the Mattis–Bardeen theory of anomalous skin effect. The modeling was used to predict the performance of a flux-flow oscillator (FFO) and a SIS frequency down-converter (mixer). It is shown that in a FFO the internal loss (quasiparticle and surface) limits flux flow to the frequency band of 260–770 GHz. A SIS junction of micron size employed as a mixer for frequency down-conversion demonstrates distributed behavior at frequencies above 550 GHz. We suggest that electrically long SIS junctions of resonant size can be used as self-compensating mixing elements with attractive performance in Nb as well as NbN mixers.

Journal of Applied Physics•Oct 15, 1996•29 citations

Terahertz high-sensitivity SIS mixer based on Nb–AlN–NbN hybrid superconducting tunnel junctions

Bo-Liang 博梁 Liu 刘, Dong 冬 Liu 刘, Ming Yao +8 more

The terahertz band, a unique segment of the electromagnetic spectrum, is crucial for observing the cold, dark universe and plays a pivotal role in cutting-edge scientific research, including the study of cosmic environments that support life and imaging black holes. High-sensitivity superconductor–insulator–superconductor (SIS) mixers are essential detectors for terahertz astronomical telescopes and interferometric arrays. Compared to the commonly used classical Nb/AlO x /Nb superconducting tunnel junction, the Nb/AlN/NbN hybrid superconducting tunnel junction has a higher energy gap voltage and can achieve a higher critical current density. This makes it particularly promising for the development of ultra-wideband, high-sensitivity coherent detectors or mixers in various scientific research fields. In this paper, we present a superconducting SIS mixer based on Nb/AlN/NbN parallel-connected twin junctions (PCTJ), which has a bandwidth extending up to 490 GHz–720 GHz. The best achieved double-sideband (DSB) noise temperature (sensitivity) is below three times the quantum noise level.

Chinese Physics B•Feb 22, 2024•5 citations

Low-Noise Superconducting Mixers for the Terahertz Frequency Range

Victor Y. Belitsky, Serguei Cherednichenko, Dag Winkler

This chapter discusses the high sensitivity superconducting mixers, i.e. detectors used in heterodyne receivers. Today, there are essentially two very successful concepts of superconducting mixers, or frequency down-converters, the superconductor-insulator-superconductor tunnel junction SIS mixer and the superconducting hot-electron bolometer mixer. Moving up to higher frequencies in the microwave and millimeter wave electromagnetic spectra makes it more and more difficult to retrieve a good signal-to-noise ratio with ordinary solid-state amplifiers. The driving force for using superconducting mixers is their excellent down-conversion efficiency and capability to down-convert RF signals from microwave frequencies up to the terahertz region. The main purpose of a receiver is to pick up and amplify a weak signal, which can then be accurately determined in amplitude and phase. The mixer noise temperature and conversion gain are the most important parameters for the mixing device. The Josephson junction mixer was one of the first suggested devices based on superconducting point contacts and later tunnel junctions.

CRC Press eBooks•May 17, 2022•1 citation
The regimes of operation of a superconductor–insulator–superconductor tunnel junction based on three-layer structures Nb/AlOx/Nb and Nb/AlN/NbN as a harmonic mixer (for frequencies of the order of 600 and 20 GHz, respectively) and a frequency up-converter (in the frequency range from 0.1 to 5.0 GHz) have been investigated experimentally. The quasiparticle and Josephson mixing regimes have been compared. It has been shown that, in some practical applications, such as the use of the superconductor–insulator–superconductor junction as a cryogenic harmonic phase detector, the Josephson mixing regime is more preferable, because it can provide a higher signal and a greater signal-to-noise ratio as compared to the quasiparticle mixing regime. It has also been demonstrated that the Josephson mixing regime is promising for the use in signal multiplexing systems for superconducting detectors.
We experimentally investigate different mixing regi-mes in Nb/AlOx/Nb and Nb/AlN/NbN tunnel superconductor-insulator-superconductor (SIS) junctions. The SIS mixers were studied with regard to the following modes of operation: in an extremely low-frequency range (0.1-20 GHz) and as high harmonic mixers; n ≈ 20-30 at signal frequencies of about 500 GHz that requires high power of a local oscillator. The quasiparticle and Josephson mixing regimes have been compared. We demonstrate that, in some applications requiring high conversion efficiency, the Josephson regime can be more preferable than the quasiparticle regime due to a larger output signal and better signal-to-noise ratio. As an example of such an application, we consider the phase locking of a THz oscillator using a cryogenic harmonic phase detector, which only ought to realize all of its benefits under the Josephson mixing regime. In addition, we demonstrate that the presence of the Josephson effect results in considerable increase in conversion efficiency at the expense of the dynamic range decrease; it was measured for low-frequency up- and down-convertors, which are promising for cryogenic multiplexing systems.
the possibility of using superconductor–insulator–superconductor (SIS) tunnel junctions in a cryogenic multiplexing system for setting an ac current through arrays of transition edge sensors and reading out the received signal, as well as for setting a dc current through arrays of superconducting quantum interferometers is studied. Operation of the SIS frequency converter at relatively low (below 10 GHz) working frequencies is experimentally investigated. Different operation regimes are implemented; the conversion loss in the quasiparticle mode is found to be 8 dB and the output saturation power is–58 dBm. The possibility of up-conversion of several input signal frequencies simultaneously is demonstrated. It is shown that the SIS junction can be used as a current source controlled by an external RF signal.
Heterodyne mixers based on superconducting SIS (superconductor-insulator-superconductor) tunnel junctions have been demonstrated to be the most sensitive coherent detectors at millimeter and submillimeter wavelengths. In fact, conventional superconducting SIS mixers with Nb/AlOx/Nb junction and Nb/SiO2/Nb tuning circuit have shown good performances with the noise temperature reaching as low as three times the quantum limit below 0.7THz, which is the gap frequency of Nb-based SIS junctions. However, due to the large loss in Nb thin-film superconducting microstrip lines, the noise performance of Nb SIS mixers deteriorates significantly above 0.7THz. With a gap frequency double that of Nb-based SIS junctions, NbN-based SIS junctions are of particular interest for the development of heterodyne mixers in the terahertz region. Considering the bandwidth and output power of local-oscillator (LO) signal sources are quite limited around 1THz, we firstly develop a waveguide NbN-based SIS mixer at 0.5THz. Three types of SIS junctions, i.e., long junction, parallel-connected tunnel junction (PCTJ) and distributed junction array (DJ) are investigated. They are all comprised of NbN-AlN-NbN tri-layer fabricated on an MgO substrate and have the same current density (Jc) of 10kA/cm2. In this paper, we describe their design, fabrication and preliminary experimental results.
The superconductor–insulator–superconductor (SIS) tunnel junction based on Nb material has been investigated theoretically at frequencies of 200–1400 GHz by modeling it as a segment of a superconducting microstrip transmission line and using the Mattis–Bardeen theory of anomalous skin effect. The modeling was used to predict the performance of a flux-flow oscillator (FFO) and a SIS frequency down-converter (mixer). It is shown that in a FFO the internal loss (quasiparticle and surface) limits flux flow to the frequency band of 260–770 GHz. A SIS junction of micron size employed as a mixer for frequency down-conversion demonstrates distributed behavior at frequencies above 550 GHz. We suggest that electrically long SIS junctions of resonant size can be used as self-compensating mixing elements with attractive performance in Nb as well as NbN mixers.
The terahertz band, a unique segment of the electromagnetic spectrum, is crucial for observing the cold, dark universe and plays a pivotal role in cutting-edge scientific research, including the study of cosmic environments that support life and imaging black holes. High-sensitivity superconductor–insulator–superconductor (SIS) mixers are essential detectors for terahertz astronomical telescopes and interferometric arrays. Compared to the commonly used classical Nb/AlO x /Nb superconducting tunnel junction, the Nb/AlN/NbN hybrid superconducting tunnel junction has a higher energy gap voltage and can achieve a higher critical current density. This makes it particularly promising for the development of ultra-wideband, high-sensitivity coherent detectors or mixers in various scientific research fields. In this paper, we present a superconducting SIS mixer based on Nb/AlN/NbN parallel-connected twin junctions (PCTJ), which has a bandwidth extending up to 490 GHz–720 GHz. The best achieved double-sideband (DSB) noise temperature (sensitivity) is below three times the quantum noise level.
This chapter discusses the high sensitivity superconducting mixers, i.e. detectors used in heterodyne receivers. Today, there are essentially two very successful concepts of superconducting mixers, or frequency down-converters, the superconductor-insulator-superconductor tunnel junction SIS mixer and the superconducting hot-electron bolometer mixer. Moving up to higher frequencies in the microwave and millimeter wave electromagnetic spectra makes it more and more difficult to retrieve a good signal-to-noise ratio with ordinary solid-state amplifiers. The driving force for using superconducting mixers is their excellent down-conversion efficiency and capability to down-convert RF signals from microwave frequencies up to the terahertz region. The main purpose of a receiver is to pick up and amplify a weak signal, which can then be accurately determined in amplitude and phase. The mixer noise temperature and conversion gain are the most important parameters for the mixing device. The Josephson junction mixer was one of the first suggested devices based on superconducting point contacts and later tunnel junctions.